Cracks in Girders Delay North Carolina Project a Second Time
North Carolina Dept. of Transportation officials hope to resume erection work on the $36.6-million Oak Island Bridge project before the end of July, once concerns about cracks found in five concrete girders are alleviated. Work on the bridge halted in early July for the second time in eight months while prime contractor Barnhill Contracting Co., Tarboro, N.C., validates the quality of the suspect girders, four of which were placed.
The bridge is part of a new 4.5-mile-long link connecting Oak Island to the mainland, south of Wilmington in Brunswick County. It consists of 160-ft-long modified bulb-tees erected as three-span continuous units. Ellis Powell, NCDOT director of field support, says potential problems were first identified at fabricator Standard Concrete Products plant in Savannah, Ga. Follow-up inspections raised more concerns.
State inspectors who viewed the girders at the fabrication plant “originally thought that it was web-splitting [cracks in the ends of the girders due to de-tensioning], and the girders were repaired,” Powell says. But additional inspections by on-site DOT engineers changed the diagnosis.
“What was initially thought to be web-splitting turned out to be a pour line,” Powell explains. “The [areas] being reviewed appear to be cold joints in the girders and at this time are considered fabrication concerns.”
He says NCDOT has taken numerous core samples. The review will involve engineering analysis by Barnhill and NCDOT. Barnhill officials are seeking validation from the fabricator.
Related roadway work is continuing. According to Powell, if Barnhill states it cannot testify to the quality of the girders, Standard Concrete Products will be required to produce replacement girders.
“If they want to talk about us using these girders, then we’ll have some more discussion,” Powell says.
Last December, work on the project stopped after a 121-ton girder fell, killing one worker. Construction did not resume until May. The state Dept. of Labor’s Division of Occupational Safety and Health cited Barnhill twice for a total of $2,800 in penalties. Lee Construction Co., the Charlotte, N.C., bridge erector, was fined $6,300.
The project’s current completion date is Dec. 31, 2009.